The last time we visited Neptune was with Voyager 2 back in 1989 ... However, a lack of data makes further speculation difficult. Triton, Neptune's moon, is also interesting in its own right.

The planet's large and unusual moon, Triton, dominates this Webb portrait as a very bright point of light. A unique view: These pictures of Neptune were obtained by NASA Voyager 2 on April 26,1989.